Reporters at Automobile.com had the chance to test drive the Mercedes Benz S400 BlueHybrid. This luxury car will be the first mass marketed vehicle to use lithium-ion batteries.

The vehicle is actually set up as a mild hybrid, which means it will stop the gas engine when not moving, will recapture kinetic energy into the battery, and will provide some electric assist on acceleration. It will not be able to drive electric-only.

It uses a 3.5 L V6 that achieves 0 to 60 in 7.2 seconds.

Fuel efficiency is expected to be 30 mpg, and the car will go on sale in the US in September 2009, likely for close to $100,000.

Source (Automobile.com)